From 8e83989106562326bfd6aaf92174fe138efd026b Mon Sep 17 00:00:00 2001 From: Deepak Sikri Date: Sun, 8 Jul 2012 21:14:45 +0000 Subject: stmmac: Fix for nfs hang on multiple reboot It was observed that during multiple reboots nfs hangs. The status of receive descriptors shows that all the descriptors were in control of CPU, and none were assigned to DMA. Also the DMA status register confirmed that the Rx buffer is unavailable. This patch adds the fix for the same by adding the memory barriers to ascertain that the all instructions before enabling the Rx or Tx DMA are completed which involves the proper setting of the ownership bit in DMA descriptors. Signed-off-by: Deepak Sikri Signed-off-by: David S. Miller --- drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'drivers/net/ethernet/stmicro') diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c index 51b3b68..ea3003e 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -1212,6 +1212,7 @@ static netdev_tx_t stmmac_xmit(struct sk_buff *skb, struct net_device *dev) priv->hw->desc->prepare_tx_desc(desc, 0, len, csum_insertion); wmb(); priv->hw->desc->set_tx_owner(desc); + wmb(); } /* Interrupt on completition only for the latest segment */ @@ -1227,6 +1228,7 @@ static netdev_tx_t stmmac_xmit(struct sk_buff *skb, struct net_device *dev) /* To avoid raise condition */ priv->hw->desc->set_tx_owner(first); + wmb(); priv->cur_tx++; @@ -1290,6 +1292,7 @@ static inline void stmmac_rx_refill(struct stmmac_priv *priv) } wmb(); priv->hw->desc->set_rx_owner(p + entry); + wmb(); } } -- cgit v1.1 From 684901a6df1fb91fc9a2bdb89ffbebb241428d78 Mon Sep 17 00:00:00 2001 From: Deepak Sikri Date: Sun, 8 Jul 2012 21:14:46 +0000 Subject: stmmac: Fix for higher mtu size handling For the higher mtu sizes requiring the buffer size greater than 8192, the buffers are sent or received using multiple dma descriptors/ same descriptor with option of multi buffer handling. It was observed during tests that the driver was missing on data packets during the normal ping operations if the data buffers being used catered to jumbo frame handling. The memory barrriers are added in between preparation of dma descriptors in the jumbo frame handling path to ensure all instructions before enabling the dma are complete. Signed-off-by: Deepak Sikri Signed-off-by: David S. Miller --- drivers/net/ethernet/stmicro/stmmac/ring_mode.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'drivers/net/ethernet/stmicro') diff --git a/drivers/net/ethernet/stmicro/stmmac/ring_mode.c b/drivers/net/ethernet/stmicro/stmmac/ring_mode.c index fb8377d..4b785e1 100644 --- a/drivers/net/ethernet/stmicro/stmmac/ring_mode.c +++ b/drivers/net/ethernet/stmicro/stmmac/ring_mode.c @@ -51,7 +51,7 @@ static unsigned int stmmac_jumbo_frm(void *p, struct sk_buff *skb, int csum) desc->des3 = desc->des2 + BUF_SIZE_4KiB; priv->hw->desc->prepare_tx_desc(desc, 1, bmax, csum); - + wmb(); entry = (++priv->cur_tx) % txsize; desc = priv->dma_tx + entry; @@ -59,6 +59,7 @@ static unsigned int stmmac_jumbo_frm(void *p, struct sk_buff *skb, int csum) len, DMA_TO_DEVICE); desc->des3 = desc->des2 + BUF_SIZE_4KiB; priv->hw->desc->prepare_tx_desc(desc, 0, len, csum); + wmb(); priv->hw->desc->set_tx_owner(desc); priv->tx_skbuff[entry] = NULL; } else { -- cgit v1.1